Cause: Haphazard steepening of slopes for
NBRO to issue new guidelines:
The National Building Research Organization (NBRO) investigations on
recent landslides have revealed that 90 percent of the reported cases
have been activated due to man-made causes. Haphazard steepening of
slopes for housing and other construction have been identified as the
cause for a majority of the slides.
Based on the findings, the NBRO is set to issue new guidelines for
development, construction and human settlement activities in landslide
prone areas. The NBRO is preparing landslide hazard zonation maps in 10
districts identified as having landslide prone areas.
The NBRO plans to provide maps detailing identified landslide prone
areas and guidelines on constructions in those areas to local decision
makers. The idea is to effectively incorporate landslide disaster risk
reduction into local planning, Landslide and Services Division Studies
head RMS Bandara said.
Ten districts have been identified by the NBRO as landslide prone
areas. They are Badulla, Nuwara Eliya, Ratnapura, Kegalle, Kandy, Matale,
Matara, Galle, Hambantota and Kalutara. Over 12,500 Kms of landslide
prone areas are spread over these 10 districts.
According to Bandara the NBRO has completed landslide hazard maps in
seven districts. The remaining three - Matara, Galle and Hambatota are
to be completed before the end of the year.
According to an NBRO report following torrential rains in November
and December 2010, and January 2011 which caused a number of slope
failures resulting in loss of lives and property, 10 teams of scientists
had been sent to investigate the 675 reported cases in six districts.
Studies on about half the cases have been completed. And among them
the NBRO has identified about 256 houses that are at high risk and about
108 houses are at medium risk. Stretches of Walapane-Padiyapelella road,
Kandy – Badulla road, Walapane – Nildandahinna road, and Haputale –
Bandarawela road have also been identified as risky.
During recent rains several houses close to a quarry near Kandy town
collapsed due to a landslide killing eight people and injuring several
The locations of both the houses and the quarry have been questioned.
The NBRO says that they investigated some of the failed sites before
hand and had recommended measures to be taken to prevent future slope
failures. Failure to implement the recommended measures was another
cause for certain slides, they added.
They say that the importance of studying the geological and
hydrological conditions of the selected sites and implementing suitable
landslide mitigation measures prior to planning and constructing of any
building is highlighted again with the occurrences of recent slope
They point out that it is time to implement the precautionery
measures which have already been formulated.